ANPH111 Coverage: Cardiovascular System - PDF

 ANPH111 COVERAGE Cardiovascular System : Blood Cardiovascular System Semen Analysis Respiratory System Lymphatic System Digestive System Reproductive System Urinary System Endocrine System  Anatomy and Physiology Chapter 10: Cardiovascular System (B...

 ANPH111 COVERAGE Cardiovascular System : Blood Cardiovascular System Semen Analysis Respiratory System Lymphatic System Digestive System Reproductive System Urinary System Endocrine System  Anatomy and Physiology Chapter 10: Cardiovascular System (Blood) — Liquid connective tissue that forms part of the cardiovascular system — Plays an important role in maintaining homeostasis in a living organism — Specialized connective tissue Plasma: fluid part (55%) Formed blood cells (45%) > Erythrocytes (RBC) > Leukocytes (WBC) > Thrombocytes (Platelets) Physical Properties of Blood 1. Average adult = 7-9% of total body weight > Male = 5-6 liters of blood > Female = 4-5 liters of blood 2. Red color of arterial blood is due to oxygenated Hgb Functions of Blood 1. Transport — 02, CO,, nutrients, waste, hormones 2. Protection — Blood can clot which prevents excessive loss of blood after an injury; — Host defense mechanism thru antibody production 3. Regulation — Circulating platelets helps maintain hemostasis in all body fluid compartments — Controls pH acid-base balance thru buffers — Albumin osmotic pressure helps retain water — Variable rate of flow of blood thru skin helps dissipate heat to the environment 4. Clotting mechanism 5. Protection against foreign microbes and toxins  The Classification of Blood Cells and the Composition of Plasma 1. Erythrocytes (RBCs) : 95% of the volume of blood cells 2. Leukocytes (WBCs) Granular: neutrophils, eosinophils, basophils Agranular: monocytes, lymphocytes 3. Thrombocytes: platelets Plasma Water of Plasma — Liquid portion of blood is 91% water — 90%, provides the solvent for dissolving and transport of — Composition of plasma: nutrients Water Plasma proteins plasma electrolytes nutrients and waste products gasses and buffers Plasma proteins Plasma Electrolyte — Synthesized mostly by hepatocytes — Inoraganic molecules that separate into ions when they are Compositions : dissolved in water 1. Albumin : Promotes water retention in the blood — Classifications: to maintain blood volume and pressure Cation — positively charged like sodium, potassium, calcium 2. Globulins: Acts as carrier molecule to transport and magnesium liquid and fat soluble vitamin in the blood (Vit. Anion — negatively charged like chloride, phosphate, iodide ADEK); Used as antibodies-immunoglobulin 3. Fibrinogen : For blood clotting ; Serum - plasma minus fibrinogen and other protein involved in clotting Nutrients & Waste products 1. Nutrients - glucose, amino acids, phospholipid, triglycerides, free fatty acids and cholesterol 2. Metabolic wastes - lactic acid, nitrogenous waste (urea) Gases & Buffers — Oxygen, nitrogen, carbon dioxide ( principal gases ) dissolved in plasma Formed Elements — Whole cell, cell fragments A. RBC - red blood cell / erythrocyte B. WBC - white blood cell C. Platelets - thrombocytes  A. Red Blood Cell — average : (M = 5.5 million/ cu.mm) (F = 4.8 million /cu.mm) RBC PHYSIOLOGY — size: 7 (micrometer ) — Biconcave disc shape provides a larger — shape: biconcave disc ( like a doughnut without a whole poked in the surface area for gas diffusion middle) — RBC consists mostly of Hgb oxygen — anucleated : no nucleus carrying globular protein — absence of cytoplasmic organelles like mitochondria and ER, thus cannot reproduce itself — contains oxygen carrying protein Hgb that gives blood its red color — plasma membrane - strong & flexible - which allows the red blood cell to be deformed as it squeezes through small capillaries without rupturing — life span : 120 days — old RBC's are removed by macrophages in spleen Mechanisms of as blood flows through capillaries: In the lungs oxygen + heme iron portion to form oxyhemoglobin When blood reaches the body tissue capillaries Hgb releases oxygen first into interstitial fluid and then to cell for its cellular metabolism Carbon dioxide, a waste product of cellular metabolism from the tissue, will bind with globin to form carbaminohemoglobin As blood flows to the lungs carbon dioxide is released by hemoglobin and then exhaled Erythropoeisis — Production of red blood cell — Site of production: red bone marrow, vertebra, ribs, sternum, upper end of humerus & femur — Hypoxia stimulates kidney to produce hormone erythropoeitin ( EPO) which in turn stimulates red bone marrow to produce RBC Circulation of RBC in Bone Marrow Bloodstream RBC Disorders — As the RBC ages CHON part of its plasma membrane anemia - oxygen carrying capacity of blood is reduced undergoes normal degradation process and becomes leaky, hemophilia - inherited deficiency of clotting in which since it has no nucleus it cannot replace the enzyme and bleeding may occur spontaneously or after a minor trauma protein lost. Ultimately, it ruptures. Fragmented particles are engulfed by macrophages in the spleen and liver and the breakdown product recycled Some Parameters in Examination for RBC Abnormalities 1. Hgb - amount of hemoglobin in blood (Male = 14-16 gm) (Female = 12-14 gm) note: Male has higher Hgb because testosterone found more in males stimulates synthesis of EPO 2. Hct - number of RBC in whole blood (Male = 45-52 %) Female = 37-48%  B. White Blood Cells — Leukocyte Chemotaxis — process by which neutrophil and other — 5,000-10,000 cells of blood WBC are attached to the chemicals released by — has nucleus microorganisms at the site of infection or injury — Do not have Hgb — less numerous and larger than RBC Diapedesis — process by which WBC leaves the — most live in few days except lymphocyte can live for bloodstream by being able to deform, elongate, squeeze several months or years through pores of capillaries to reach injured tissue — combats pathogen by phagocytosis and immune response — once granulocyte and monocyte leave the bloodstream to tight injury or intection they never return to the bloodstream Types of WBC — lymphocyte : continuously recirculate when it leaves 1. Granular Leukocyte the bloodstream goes into the interstitial fluid to lymphatic 2. Agranular Leukocyte fluid back to bloodstream; very small percent circulate in the bloodstream; mostly they are found in the lymphatic fluid and lymphatic organs 1. Granular Leukocyte — Named after their affinity to dye / stain (Wright ) — Segmented or multilobulated nuclei —Has granules in the cytoplasm — Types of Granular: Neutrophil Eosinophil Basophil Neutrophil Eusinophil — 60-70% of the WBC PMN — 2-4% of WBC — Most abundant of the WBC — Nucleus: 2-3 lobes — Nucleus: 3-5 lobes — Larger uniform-sized granules than neutrophils — Connected by a very thin strand of chromatin — Granules contain lysozymes, peroxidase to destroy — Released in blood in band form – young neutrophil intruders — Barr body – inactive X chromosome found only in females, — Stains pink in acidic dyes important in sex identification — Phagocytizes Ag-Ab complexes — First line of defense – responds quickly to bacterial infection — Destroys certain parasitic worms — Fine granules evenly distributed in the cytoplasm; contains — Combats the effects of histamine in allergic lysozyme. reactions by releasing histaminase — Stains neutral pink-blue. — In the process of phagocytosis, granules are depleted. Neutrophil dies together with microorganisms and forms pus (yellowish material). Basophil — 0.5 - 1% — Coarse large granules which stain dark blue obscuring — S-shaped nucleus — Liberates heparin ( anticoagulant ); slow reacting substance of anaphylaxis SRS-A  2. Agranular Leukocytes — No granules — Have unsegmented nucleus — Types of Agranular: lymphocyte monocyte Lymphocyte Monocyte — 20-25% — 3.8% — 2nd most abundant leukocyte — Kidney shaped nucleus — Round slightly indented nucleus — Largest of formed elements — Cytoplasm forms a rim around the nucleus — Stays in the bloodstream only for 3 days — Not phagocytic — Capable of phagocytosis as it transforms to — They are produced in the bone marrow and lymphoid tissue macrophages — Seen in acute viral infection and chronic bacterial infection — Produces antibodies — Types of Lymphocyte: B-Cell, T-Cell, NK (Natural Killer) Cell Leukopoiesis C. Platelets — Platelet - thrombocyte — Megakaryocytes → platelets ( thrombocytes ) — 150,000 400,000 cell of blood — Disk-shaped cell fragments — No nucleus — Lifespan 7-8 days — Not actually blood cells but cellular fragments — Aged platelets are removed by macrophages — Platelet when it enters the bloodstream picks-up and stores chemical substances that can be released later to help seal blood vessel breaks — Thrombopoiesis : The process of platelet formation/production. Hemostasis — The prevention of blood loss  Mechanisms Involved 1. Vasoconstrictive Phase — when tissue is damaged and blood vessel breaks immediately the blood vessel muscular wall constricts to prevent further loss of blood 2. Platelet Phase : A. Platelet Adhesion — initially when tissue is injured platelet migrate attach themselves to the collagen fiber of connective tissue underlying the damaged area B. Platelet Aggregation — as more platelet sticks together at the damaged area they become more sticky eventually forming a platelet plug. As they interact with one another they release substances from their vesicle like serotonin, which constricts the vascular smooth muscles, which decreases the blood flow and stop the bleeding. Injured blood vessel may continue to constrict only for about 20 mins. If the injury is extensive, the intricate mechanism of clotting continues The Clotting Mechanism Clot — Fibrin forms long threads acting like a net; Platelets get enmeshed Syneresis — clot retraction Fibrinolysis — dissolution of blood clot Thrombosis — unwanted clotting Embolus — circulating blood clot Infarction — Tissues killed as a result of loss of blood supply RH SYSTEM Discovered first in Rhesus monkeys = Rh Factor. D antigen: Most important in the production of antibodies. People whose RBCs have Rh antigen are designated as Rh (+); those without are Rh (-). Normally, plasma does not contain Rh antibodies. However, in Rh-negative individuals, the immune system produces anti-Rh antibodies after exposure to Rh-positive blood. Subsequent transfusion of Rh-positive blood into Rh-negative individuals can cause hemolysis (rupture) of RBCs due to preformed anti-Rh antibodies Examples: 1. Mother is Rh (-), Father is Rh (+): Formation of Rh antibodies in the mother’s blood. The first fetus (Rh-positive) is not harmed. In subsequent pregnancies, if the fetus is Rh-positive, hemolysis may occur due to Rh antibodies from the mother attacking the fetal RBCs. Results in Hemolytic Disease of the Newborn (Erythroblastosis fetalis).  Homeostasis: Maintaining the body’s internal environment within physiological limits. Hemostasis: Stoppage of bleeding. Blood Typing: 1. Type A donor + Anti-B antibodies in Type A recipient: No agglutination (no reaction). 2. Type A donor + Anti-A antibodies in Type B recipient: Agglutination (reaction occurs). Blood Typing Results: Chart for interpreting blood type using Anti-A, Anti-B, Anti-D, and Control reagents. Positive agglutination indicates the presence of specific antigen  CHAPTER 11: CARDIOVASCULAR SYSTEM — body’s transport system — A closed system of the heart and blood vessels > The heart pumps blood > Blood vessels allow blood to circulate to all parts of the body — The function of the cardiovascular system is to deliver oxygen and nutrients and to remove carbon dioxide and other waste products The Heart — Located at the thorax (Mediastinum) bet ween the lungs. — Apex directed toward left hip, rests diaphragm 5th ICS — Base towards right shoulder, 2nd rib. — About the size of your fist — Less than 1 lb. The Heart: Coverings — Pericardium : a double serous membrane > Visceral pericardium : Next to heart > Parietal pericardium : Outside layer — Serous fluid fills the space bet ween the layers of pericardium The Heart: Heart Wall Three layers: 1. Epicardium — Outside layer — This layer is the parietal pericardium — Connective tissue layer 2. Myocardium — Middle layer — Mostly cardiac muscle 3. Endocardium — Inner layer — Endothelium The Heart: Chambers Four chambers note: Right and left I Atria side act as separate — Receiving chambers pumps — Right atrium — Left atrium Ventricles — Discharging chambers — Right ventricle 77 t — Left ventricle  EXTERNAL HEART ANATOMY BLOOD CIRCULATION The Heart: Valves — Allow blood to flow in only one direction — Valves open as blood is pumped through — Held in place by chordae tendineae ("heart strings") — Close to prevent blood backflow Four Valves: Atrioventricular valves — bet ween atria and ventricles — Bicuspid valve (left) — Tricuspid valve (right) Semilunar valves — bet ween ventricle and artery — Pulmonary semilunar valve — Aortic semilunar valve  Operation of Heart Valves Valve Pathology — Incompetent valve backflow and repump — Stenosis = stiff = heart workload increased may be replaced — Lub Dub Heart Sound — note: Stenosis is the term for a valve that doesn't open properly.. As a result, the valve cannot fully open. Thus, the heart has to work harder to pump blood through the valve, and the body may suffer from a reduced supply of oxygen. The Heart: Associated Great Vessels Aorta — Leaves left ventricle Pulmonary arteries — Leave right ventricle Vena cava — Enters right atrium Pulmonary veins (four) — Enter left atrium Coronary Circulation — Coronary circulation is the circulation of blood in the blood vessels that supply the heart muscle (myocardium). — Blood in the heart chambers does not nourish the myocardium — The heart has its own nourishing circulatory system: > Coronary arteries > Cardiac veins > Blood empties into the right atrium via the coronary sinus  Cardiac Pathology The Heart Rapid heart beat = Inadequate blood — Intrinsic conduction system (nodal = Angina Pectoris system) — medical term for chest pain or discomfort due to coronary — Heart muscle cells contract, without heart disease. ner ve impulses, in a regular, continuous — It occurs when the heart muscle doesn't get as much blood way as it needs. — This usually happens because one or more of the heart's arteries is narrowed or blocked, also called ischemia. The Heart: Conduction System — Special tissue sets the pace > Sinoatrial node (right atrium) : Pacemaker > Atrioventricular node : junction of right and left atria and ventricles) > Atrioventricular bundle (Bundle of His) : a heart muscle that takes part in electrical conduction in the heart. > Bundle branches (right and left) : Conducts impulses to the ventricles. > Purkinje fibers : it carries electrical impulse to the ventricles. Heart Contractions Electrocardiograms (EKG/ECG) Three formations 1. P wave: impulse across atria 2. QRS complex: spread of impulse down septum, around ventricles in Purkinje fibers 3. T wave: end of electrical activity in ventricles Pathology of the Heart Damage to AV node = release of ventricles from control = slower heart beat (Slower heart beat can lead to fibrillation) Fibrillation = lack of blood flow to the heart Tachycardia = more than 100 beats/min Bradycardia = less than 60 beats/min  The Heart: Cardiac Cycle Atria contract simultaneously Atria relax, then ventricles contract Systole = contraction Diastole = relaxation The Heart: Cardiac Output Cardiac output (CO) CO = HR x SV — Amount of blood pumped by each side of the heart 5250 ml/min = 75 beats/min x 70 mls/beat in one minute Norm = 5000 ml/min — CO = (heart rate [HR]) x (stroke volume [SV]) Entire blood supply passes through body once per minute. Stroke volume CO varies with demands of the body. — Volume of blood pumped by each ventricle in one contraction The Heart: Regulation of Heart Rate — Stroke volume usually remains relatively constant > Starling's law of the heart : the more that the cardiac muscle is stretched, the stronger the contraction — Changing heart rate is the most common way to change cardiac output Increased heart rate: Decreased heart rate: — Sympathetic ner vous system — Parasympathetic ner vous system > Crisis > High blood pressure or blood volume > Low blood pressure — Decreased venous return — Hormones — In Congestive Heart Failure the heart is worn > Epinephrine out and pumps weakly. Digitalis works to provide a > Thyroxine slow, steady, but stronger beat. — Exercise — Decreased blood volume Congestive Heart Failure (CHF) — Decline in pumping efficiency of heart — Inadequate circulation — Progressive, also coronary atherosclerosis, high blood pressure and history of multiple Myocardial Infarctions — Left side fails = pulmonary congestion and suffocation — Right side fails = peripheral congestion and edema  Blood Vessels: — The Vascular System — Taking blood to the tissues and back Arteries Arterioles Capillaries Venules Veins Blood Vessels: Anatomy Three layers (tunics): 1. Tunic intima — Endothelium 2. Tunic media — Smooth muscle ; Controlled by sympathetic nervous system 3. Tunic external — Mostly fibrous connective tissue Differences Between Blood Vessel Types — Walls of arteries are the thickest — Lumens of veins are larger — Skeletal muscle "milks" blood in veins toward the heart — Walls of capillaries are only one cell layer thick to allow for exchanges bet ween blood and tissue Movement of Blood Through Vessels — Most arterial blood is pumped by the heart — Veins use the milking action of muscles to help move blood Capillary Beds Capillary beds consist of two types of vessels 1. Vascular shunt — directly connects an arteriole to a venule 2. True capillaries — exchange vessels — Oxygen and nutrients cross to cells — Carbon dioxide and metabolic waste products cross into blood  Diffusion at Capillary Beds Vital Signs Arterial pulse Blood pressure Respiratory Rate Body Temperature All indicate the efficiency of the system Pulse Pulse — pressure wave of blood — Monitored at "pressure points" where pulse is easily palpated Blood Pressure — Measurements by health professionals are made on the pressure in large arteries — Systolic : pressure at the peak of ventricular contraction — Diastolic : pressure when ventricles relax — Pressure in blood vessels decreases as the distance away from the heart increases Blood Pressure: Effects of Factors Variations in Blood Pressure Neural factors Human normal range is variable — Autonomic nervous system adjustments. (sympathetic division) Normal Renal factors — less than 120 mm Hg systolic — Regulation by altering blood volume — 80-75 mm Hg diastolic — Renin - hormonal control Temperature Hypotension — Heat has a vasodilation effect — Low systolic (below 110 mm HG) — Cold has a vasoconstricting effect — Often associated with illness Chemicals — Various substances can cause increases or decreases Hypertension Diet — High systolic (above 140 mm HG) — Can be dangerous if it is chronic Chapter 12: Semen Analysis — A semen analysis measures the amount of sperm a man produces and determines the number and quality of sperm in the semen sample. — A semen analysis is usually one of the first test done to help determine whether a man has a problem fathering a child (infertility). — A problem with the semen or sperm affects more than one-third of the couples who are unable to have children (infertile). Semen Analysis — Semen Analysis are mainly carried out to determine whether:- — A man has a reproductive problem that is causing infertility. — A vasectomy or vasectomy reversal has been successful — Semen Analysis is the singular test for fertility in male that can provide information on > sperm production. > patency of the male ducts. > the function of the accessory glands. > and ejaculative function. — Since semen samples may vary from day, 2 or 3 samples may be evaluated within a 3-6 month period for accurate testing — A semen analysis to test the effectiveness of a vasectomy is usually done 6 weeks after the vasectomy Semen Collection — Masturbation, directing the semen into a clean sample cup. Do not use a lubricant which can kill sperms — Coitus interruptus - withdrawing the penis from the partner just before ejaculating follow by ejaculating into a clean sample cup. — Coitus by using a condom. A special (silicon) condom that does not contain any substance that kills sperm (spermicide). After ejaculation, carefully remove the condom from the penis. Tie a knot in the open end of the condom and place it in a container that can be sealed in case the condom leaks or breaks. Ordinary condoms should not be used since they usually contain spermicides — Assisted ejaculation - electro-ejaculation used in paralegics Good and reliable SA results starts from semen collection, preferably by masturbation > Abstinence days 2-5 days > Pass urine > Wash hands with soap, dry > Collect the entire sample into the wide mouth sterile container, 70% of sperms is in the first part of the ejaculate > Keep the sample at body temperature, no sunlight > Deliver the sample within one hour ejaculation Procedure 1. Once sample is collected, receiving time is note down. 2. The sample has to be liquefied for 20-30 min at 37 degrees C by placing the sample in heating block (or inside the pocket). 3. After leaving for 20-30 mins of liquefaction, mix the sample homogeneously by using transfer pipette. 4. Macroscopic observation of sample's color, odor, volume, viscosity and pH should be noted. Parameters- Lower Reference Limits Semen Volume - 1.5 ml Sperm concentration (106/ml) - 15 x 106/ml Total sperm number (10%/ejaculate) - 39 x 10% ejaculate Progressive motility (PR, %) - 32% Total motility (PR +NP, %) - 40% Vitality (live sperms, %) - 58% Sperm morphology (NF, %) - 4 pH - equal or greater than 7.2  Basic Terminologies Oligospermia — sperm concentration 1 M/ml Hematospermia — red blood cell present in semen Necrozoospermia — "dead" sperm WHO criteria (2010) Macroscopic examination Normal Color: Whitish to grey opalescent (pearl white) Normal Liquefaction: 15-30 min after collection Normal Viscosity : Smooth and watery Normal Volume : 1.5 ml per ejaculation Normal ph : ≥ 7.2 (Alkaline) Microscopic Examination Sperm Count: 1. A microscope objective 20x should be used for counting 2. Place a drop of sample into Makler chamber and count the sperm heads as follows: 10 squares of the field. This number represents the concentration of spermatozoa in millions per milliliter. (Alternative: at 400x total magnification power, count the sperm per field of view, them multiply to 500,000) 3. Count for all progressive (PR), non-progressive (NP), and immotile (IM). Calculate for the percentage for PR, NP, IM. Motility: Grade A (fast progressive) — sperms are those which swim for ward fast in a straight line - like guided missiles. Grade B (slow progressive) — sperms swim for ward, but either in a cur ved or crooked line, or slowly (slow linear or non linear motility). Grade C (non-progressive) — sperms move their tails, but do not move for ward (local motility only). Grade D (immotile) — sperms do not move at all. Sperm Morphology: A Normal Sperm has: — A smooth, oval-shaped head that is 5-6 micrometers long and 2.5-3.5 — Micrometers wide (less than the size of a needle point) A well-defined cap (acrosome) that covers 40% to 60% of the sperm head — No visible abnormality of neck, mid-piece, or tail No fluid droplets in the sperm head that are bigger than one half of the sperm head size.  Chapter 13: Respiratory System Consists of the respiratory and conducting zones Respiratory zone — Site of gas exchange — Consists of bronchioles, alveolar ducts, and alveoli Conducting zone — Includes all other respiratory structures (e.g., nose, nasal cavity, pharynx, trachea) — Respiratory muscles : diaphragm and other muscles that promote ventilation Major Functions of the Respiratory System To supply the body with oxygen and dispose of carbon dioxide Respiration : four distinct processes must happen 1. Pulmonary ventilation - moving air into and out of the lungs 2. External respiration - gas exchange bet ween the lungs and the blood 3. Transport - transport of oxygen and carbon dioxide bet ween the lungs and tissues 4. Internal respiration - gas exchange bet ween systemic blood vessels and tissues Function of the Nose Nose The only externally visible part of the respiratory system — External portion that functions by: — mainly cartilage attached to nasal bones > Providing an air way for respiration — Nostrils — external nares > Moistening and warming the entering air — Vestibules — just inside external nares > Filtering inspired air and cleaning it of foreign matter > Housing the olfactory receptors Nasal Cavity Respiratory mucosa — Lines the balance of the nasal cavity — Glands secrete mucus containing lysozyme to help destroy bacteria  Pharynx — Funnel-shaped tube of skeletal muscle that connects to the: It is divided into three regions: > Nasal cavity and mouth superiorly 1. Nasopharynx > Larynx and esophagus inferiorly 2. Oropharynx — Extends from the base of the skull to the level of the sixth 3. Laryngopharynx cervical vertebra 1. Nasopharynx — Lies posterior to the nasal cavity, inferior to the sphenoid, and superior to the level of the soft palate — Strictly an air passageway — Lined with pseudostratified columnar epithelium — Closes during swallowing to prevent food from entering the nasal cavity — The pharyngeal tonsil (adenoid) lies high on the posterior wall — Pharyngotympanic (auditory) tubes open into the lateral walls 2. Oropharynx — Extends inferiorly from the level of the soft palate to the epiglottis — Ser ves as a common passageway for food and air — The epithelial lining is protective stratified squamous epithelium — Fauces - opening toward the mouth — Palatine tonsils — Lingual tonsil 3. Laryngopharynx — Serves as a common passageway for food and air — Lies posterior to the upright epiglottis — Extends to the larynx, where the respiratory and digestive pathways diverge Larynx (Voice box) — Attaches to the hyoid bone and opens into the Larynx Cartilages laryngopharynx superiorly thyroid cartilage — (Adam's apple) — Continuous with the trachea posteriorly epiglottis — covers larynx to route food glottis - vocal folds (cords) for sound Framework of the Larynx cricoid cartilage — attaches larynx to trachea Made up of 9 segments of cartilage: arytenoid cartilage — attached to vocal folds 1. Unpaired - thyroid, epiglottic, cricoid 2. Paired - arytenoid, corniculate, cuneiform  Voice Production A. Ventricular folds (false cords) : hold breath against thoracic air pressure B. Vocal cords (true cords) : vibrate to produce different frequencies C. pharynx, mouth, sinuses, nose, tongue, lips : alter the sound Trachea 1. larynx — > T5 ; anterior to the esophagus Mucosa — made up of goblet cells and ciliated epithelium 2. C-shaped hyaline cartilage along the esophagus Submucosa — connective tissue deep to the mucosa 3. Carina — ridge at the bifurcation to the bronchi Adventitia — outermost layer made of C-shaped rings of 4. Intubation — tube down collapsed trachea hyaline cartilage 5. Tracheostomy — hole in trachea; bypass obstructions Bronchi — Air reaching the bronchi is: > Warmed and cleansed of impurities > Saturated with water vapor — Bronchi subdivide into secondary bronchi, each supplying a lobe of the lungs — Air passages undergo 23 orders of branching in the lungs Conducting Zone: Bronchial Tree — Tissue walls of bronchi mimic that of the trachea Bronchioles: — As conducting tubes become smaller, structural changes occur: — Consist of cuboidal epithelium > Cartilage support structures change — Have a complete layer of circular smooth muscle > Epithelium types change — Lack cartilage support and mucus-producing cells > Amount of smooth muscle increases  Respiratory Zone — Defined by the presence of alveoli; begins as terminal bronchioles feed into respiratory bronchioles — Respiratory bronchioles lead to alveolar ducts, then to terminal clusters of alveolar sacs composed of alveoli — Approximately 300 million alveoli: > Account for most of the lungs' volume > Provide tremendous surface area for gas exchange Lungs Cardiac notch (impression) — cavity that accommodates the Left lung — separated into upper and lower lobes by the oblique fissure Right lung — separated into three lobes (superior, middle, inferior) by the oblique and horizontal fissures Pleurae — Thin, double-layered serosa: Parietal pleura Visceral pleura — Covers the thoracic wall and superior face of the — Covers the external lung surface diaphragm — Divides the thoracic cavity into three chambers — Continues around heart and bet ween lungs — The central mediastinum — Two lateral compartments, each containing a lung Homeostatic Imbalance Chronic obstructive pulmonary disease (COPD) — is airflow limitation caused by an inflammatory response to inhaled toxins, often cigarette smoke. — Alpha-1 antitrypsin deficiency and various occupational exposures are less common causes in nonsmokers. — Symptoms are productive cough and dyspnea that develop over years; common signs include decreased breath sounds, prolonged expiratory phase of respiration, and wheezing. — Various factors cause the airflow limitation and other complications of COPD. Treatment: — Smoking cessation — Inhaled bronchodilators, corticosteroids, or both, — Supportive care (eg, oxygen therapy, pulmonary rehabilitation)  Treatment: Inhaled bronchodilators, corticosteroids Beta-agonists — relax bronchial smooth muscle and increase mucociliary clearance. — Albuterol aerosol, 2 puffs (90 to 100 mcg/puff) inhaled from a metered-dose inhaler 4 to 6 times a day as needed, is usually the drug of choice. Anticholinergics (antimuscarinics) — relax bronchial smooth muscle through competitive inhibition of muscarinic receptors (M1, M2, and M3). — Ipratropium is a short-acting anticholinergic; dose is 2 to 4 puffs (17 mcg/puff) from a metered-dose inhaler every 4 to 6 hours. — Ipratropium has a slower onset of action (within 30 minutes; peak effect in 1 to 2 hour), so a beta- agonist is often prescribed with it in a single combination inhaler or as a separate as-needed rescue drug. Homeostatic Imbalance Asthma — a disease of diffuse air way inflammation caused by a variety of triggering stimuli resulting in partially or completely reversible bronchoconstriction. — Symptoms and signs include dyspnea, chest tightness, cough, and wheezing. Treatment: — In patients with asthma, TH2 cells and other cell types-notably, eosinophils Control of triggers and mast cells, but also other CD4+ subtypes and neutrophils-form an extensive Drug therapy inflammatory infiltrate in the air way epithelium and smooth muscle, leading to Monitoring air way remodeling (ie, desquamation, subepithelial fibrosis, angiogenesis, smooth Patient education muscle hypertrophy). Treatment of acute exacerbations — Hypertrophy of smooth muscle narrows the air ways and increases reactivity to allergens, infections, irritants, parasympathetic stimulation (which causes release of pro-inflammatory neuropeptides, such as substance P, neurokinin A, and calcitonin gene-related peptide), and other triggers of bronchoconstriction. Drug Therapy (Treatment) — Major drug classes commonly used in the treatment of asthma and asthma exacerbations include: > Bronchodilators (beta-2 agonists, anticholinergics) > Corticosteroids > Leukotriene modifiers > Mast cell stabilizers > Methylxanthines > Immunomodulators — Drugs in these classes (see table Drug Treatment of Chronic Asthma) are inhaled, taken orally, or injected subcutaneously or intravenously; inhaled drugs come in aerosolized and powdered forms. — Use of aerosolized forms with a spacer or holding chamber facilitates deposition of the drug in the air ways rather than the pharynx; patients are advised to wash and dry their spacers after each use to prevent bacterial contamination. — In addition, use of aerosolized forms requires coordination bet ween actuation of the inhaler (drug delivery) and inhalation; powdered forms reduce the need for coordination, because drug is delivered only when the patient inhales. For details, see Drug Treatment of Asthma. Community-acquired pneumonia — is defined as pneumonia that is acquired outside the hospital. Treatment — The most commonly identified pathogens are Streptococcus Risk stratification for determination pneumoniae, Haemophilus influenzae, atypical bacteria (ie, of site of care Chlamydia pneumoniae, Mycoplasma pneumoniae, Legionella Antibiotics species), and viruses. Antivirals for influenza or varicella — Symptoms and signs are fever, cough, sputum production, Supportive measure pleuritic chest pain, dyspnea, tachypnea, and tachycardia.  Chapter 14: Lymphatic System and Body Defenses TWO PARTS: Characteristics of the Lymphatic System 1. Lymphatic vessels Lymph — excess tissue fluid carried by lymphatic vessels 2. Lymphoid tissues and organs Properties of lymphatic vessels: LYMPHATIC SYSTEM FUNCTION: > One-way system toward the heart Transport fluids back to the blood > No pump Play essential roles in body defense > Lymph moves toward the heart and resistance to disease > Milking action of skeletal muscle Absorb digested fat at the intestinal > Rhythmic contraction of smooth muscle in vessel walls villi LYMPHATIC VESSELS Lymphatic collecting vessels: — Collects lymph from lymph capillaries — Carries lymph to and away from lymph nodes — Returns fluid to circulatory veins near the heart by the: > Right lymphatic duct > Thoracic duct LYMPH Materials returned to the blood: Harmful materials that enter lymph vessels: — Water — Bacteria — Blood cells — Viruses — Proteins — Cancer cells — Cell debris LYMPH nodes — Filter lymph before it is returned to the blood — Defense cells within lymph nodes: > Macrophages - engulf and destroy foreign substances > Lymphocytes - provide immune response to antigens Structure of a Lymph Node Efferent Vessels — exit lymph node at the hilum Afferent Vessels — enter lymph node at various locations Trabeculae — divide the node into compartments Germinal centers of compartments — produce lymphocytes  Other Lymphoid Organs Several other organs contribute to lymphatic function: — Spleen — Thymus — Tonsils — Peyer's patches SPLEEN Located on the left side of the abdomen Functions: — Filters blood — Destroys worn out blood cells — Forms blood cells in the fetus — Acts as a blood reser voir Thymus Located low in the throat, overlying the heart Functions at peak levels only during childhood Produces hormones (like thymosin) to program lymphocytes tonsils — Small masses of lymphoid tissue around the pharynx — Trap and remove bacteria and other foreign materials — Tonsillitis is caused by congestion with bacteria Peyer's Patches — Found in the wall of the small intestine — Resemble tonsils in structure — Capture and destroy bacteria in the intestine Mucosa-Associated Lymphatic Tissue (MALT) Includes: — Peyer's patches — Tonsils — Other small accumulations of lymphoid tissue Acts as a guard to protect respiratory and digestive tracts  Body Defenses — The body is constantly in contact with bacteria, fungi, and viruses (pathogens) — The body has t wo defense systems for foreign materials: Nonspecific and Specific. Nonspecific Defense System Specific Defense System Mechanisms protect against a variety of invaders Specific defense is required for each type. Responds immediately to protect body from foreign of invader materials Also known as the immune system Examples: — Body surface coverings > Intact skin > Mucous membranes — Specialized human cells — Chemicals produced by the body Surface Membrane Barriers - First Line of Defense The skin — Physical barrier to foreign materials — pH of the skin is acidic to inhibit bacterial growth > Sebum is toxic to bacteria > Vaginal secretions are very acidic Stomach mucosa — Secretes hydrochloric acid — Has protein-digesting enzymes — Saliva and lacrimal fluid contain lysozyme — Mucus traps microorganisms in digestive and respiratory pathways DEFENSIVE CELLS Phagocytes — (neutrophils and macrophages) — Engulfs foreign material into a vacuole — Enzymes from lysosomes digest the material Natural Killer Cells — (neutrophils and macrophages) — Engulfs foreign material into a vacuole — Enzymes from lysosomes digest the material Inflammatory Response - Second Line of Defense Triggered when body tissues are injured Produces four cardinal signs: Redness, Heat, Swelling, Pain Results in a chain of events leading to protection and healing  Functions of the Inflammatory Response — Prevents spread of damaging agents — Disposes of cell debris and pathogens — Sets the stage for repair Antimicrobial Chemicals Complement — A group of at least 20 plasma proteins — Activated when they encounter and attach to cells (complement fixation) — Damage foreign cell surfaces — Will rupture or lyse the foreign cell membrane Interferon — Secreted proteins of virus-infected cells — Bind to healthy cell surfaces to inhibit viruses binding — Interferons are a family of species-specific proteins synthesized by eukaryotic cells in response to viruses and a variety of natural and synthetic stimuli. — There are several different interferons commonly used as therapeutics, termed alpha, beta, and gamma. — These peptides are used to treat hairy cell leukemia, AIDS-related Kaposi’s sarcoma, laryngeal papillomatosis, genital warts, and chronic granulomatous disease. Side effects include black tarry stools, blood in the urine, confusion, and loss of balance. Fever — Abnormally high body temperature. — Hypothalamus heat regulation can be reset by pyrogens (secreted by white blood cells). — High temperatures inhibit the release of iron and zinc from the liver and spleen, needed by bacteria. — Fever also increases the speed of tissue repair. Specific Defense: The Immune System —: Third Line of Defense Types of Immunity Antigen-specific - recognizes and acts against foreign Humoral immunity substances — Antibody-mediated immunity Systemic - not restricted to the initial infection site — Cells produce chemicals for defense Has memory - recognizes and mounts a stronger attack on Cellular immunity previously encountered pathogens — Cell-mediated immunity — Cells target virus infected cells Antigens (Nonself) Self-Antigens Any substance capable of exciting the immune system and Human cells have many surface proteins provoking an immune response Our immune cells do not attack our own proteins Examples of common antigens: Our cells in another person's body can trigger an — Foreign proteins immune response because they are foreign; Restricts — Nucleic acids donors for transplants — Large carbohydrates — Some lipids — Pollen grains — Microorganisms  Allergies — Many small molecules (called haptens or incomplete antigens) are not antigenic, but link up with our own proteins — The immune system may recognize and respond to a protein-hapten combination — The immune response is harmful rather than protective because it attacks our own cells Some Symptoms of an Allergic Reaction: — Hives, itching, and swelling in areas other than the sting site. — Tightness in the chest and difficulty in breathing. — Hoarse voice or swelling of the tongue. — Dizziness or a sharp drop in blood pressure. — Unconsciousness or cardiac arrest. Cells of the Immune System Lymphocytes — Originate from hemocytoblasts in the red bone marrow — B lymphocytes become immunocompetent in the bone marrow — T lymphocytes become immunocompetent in the thymus Macrophages — Arise from monocytes — Become widely distributed in lymphoid organs Humoral (Antibody-Mediated) Immune Response — B lymphocytes with specific receptors bind to a specific antigen — The binding event activates the lymphocyte to undergo clonal selection — Many clones are produced (primary humoral response) — Most B cells become plasma cells > Produce antibodies to destroy antigens > Activity lasts for four or five days — Some B cells become long-lived memory cells (secondary humoral response) Active Immunity Passive Immunity — Your B cells encounter antigens and produce — Antibodies are obtained from someone else antibodies > Conferred naturally trom a mother to her fetus — Active immunity can be naturally or > Conferred artificially from immune serum or gamma artificially acquired globulin — Immunological memory does not occur — Protection provided by, "borrowed antibodies Antibodies (Immunoglobulins/gs) and Their Classes — Soluble proteins secreted by B cells (plasma cells) — Carried in blood plasma — Capable of binding specifically to an antigen — Antibodies of each class have slightly different roles — Five major immunoglobulin classes - IgM - can fix complement IgA - found mainly in mucus IgD - important in activation of B cell IgG - can cross the placental barrier IgE - involved in allergies  Cellular (Cell-Mediated) Immune Response — Antigens must be presented by macrophages to an immunocompetent T cell (antigen presentation) — T cells must recognize nonself and self (double recognition) — After antigen binding, clones form as with B cells, but different classes of cells are produced T Cell Clones Cytotoxic T cells Suppressor T cells — Specialize in killing infected cells — Release chemicals to suppress the — Insert a toxic chemical (perforin) activity of T and B cells — Stop the immune response to prevent Helper T cells uncontrolled activity — Recruit other cells to fight the invaders — A few members of each clone are — Interact directly with B cells memory cells Organ Transplants and Rejection Major types of grafts Autografts - tissue transplanted from one site to another on the same person Isografts - tissue grafts from an identical person (identical t win) Allografts - tissue taken from an unrelated person Xenografts - tissue taken from a different animal species Autografts and isografts are ideal donors Xenografts are never successful Allografts are more successful with a closer tissue match Disorders of Immunity: Immunodeficiencies — Production or function of immune cells or complement is abnormal — May be congenital or acquired — Includes AIDS - Acquired Immune Deficiency Syndrome Disorders of Immunity: Autoimmune Diseases — The immune system does not distinguish bet ween self and nonself — The body produces antibodies and sensitized T lymphocytes that attack its own tissues Multiple sclerosis :white matter of brain and spinal cord are destroyed Myasthenia gravis : impairs communication bet ween ner ves and skeletal muscles Juvenile diabetes : destroys pancreatic beta cells that produce insulin Rheumatoid arthritis : destroys joints Systemic lupus erythematosus (SLE) : affects kidney, heart, lung and skin Glomerulonephritis : impairment of renal function  Immune Deficiency: AIDS Acquired Immunodeficiency Syndrome — HIV targets cells — Retrovirus attaches to CD4 receptors of T helper cells — Transmission: Body fluids, i.e., blood, semen, breast milk, vaginal secretions The Human Immunodeficiency Virus (HIV) and Its Structure Time Course of the Progression of AIDS after HIV Infection Phase I: Few weeks to a few years; flu-like symptoms, swollen lymph nodes, chills, fever, fatigue, body aches. Virus is multiplying, antibodies are made but ineffective for complete virus removal. Phase II: Within six months to 10 years; opportunistic infections present, Helper T cells affected, 5% may not progress to the next phase. Phase III: Helper T cells fall below 200 per cubic millimeter of blood AND the person has an opportunistic infection or type of cancer. Person is now termed as having “AIDS.” May include pneumonia, meningitis, tuberculosis, encephalitis, Kaposi’s sarcoma, and non-Hodgkin’s lymphoma. AIDS Pandemic More than 36 million infected with HIV worldwide. Most infections in sub-Saharan Africa. Increasing spread in Asia and India. Most often spread by heterosexual contact outside the U.S.  CHAPTER 15: DIGESTIVE SYSTEM The alimentary canal or gastrointestinal (GI) tract digests and absorbs food Alimentary canal — mouth, pharynx, esophagus, stomach, small intestine, and large intestine Accessory digestive organs — teeth, tongue, gallbladder, salivary glands, liver, and pancreas Digestive Process The GI tract is a "disassembly" line: Nutrients become more available to the body in each step There are six essential activities: 1. Ingestion 2. Propulsion 3. Mechanical digestion 4. Chemical digestion 5. Absorption 6. Defecation Gastrointestinal Tract Activities 1. Ingestion — taking food into the digestive tract 2. Propulsion — swallowing and peristalsis; Peristalsis - waves of contraction and relaxation of muscles in the organ walls 3. Mechanical digestion — chewing, mixing, and churning food 4. Chemical digestion — catabolic breakdown of food 5. Absorption — movement of nutrients from the GI tract to the blood or lymph 6. Defecation — elimination of indigestible and unabsorbed solid wastes Peritoneum and Peritoneal Cavity Peritoneum — serous membrane of the abdominal cavity — Visceral peritoneum : covers external surface of most digestive organs — Parietal peritoneum : lines the body wall Peritoneal cavity — Lubricates digestive organs — Allows them to slide across one another Mesentery — double layer of peritoneum that provides: > Vascular and ner ve supplies to the viscera > A means to hold digestive organs in place and store fat  Blood Supply: Splanchnic Circulation Arteries and the organs they serve include: — The hepatic, splenic, and left gastric: spleen, liver, and stomach — Inferior mesenteric and superior mesenteric: small and large intestines Hepatic portal circulation: — Collects nutrient-rich venous blood from the digestive viscera — Delivers this blood to the liver for metabolic processing and storage Histology of the Alimentary Canal From esophagus to the anal canal the walls of the GI tract have the same four tunics. From the lumen out ward they are the: 1. Mucosa 2. Submucosa 3. Muscularis Externa 4. Serosa Each tunic has a predominant tissue type and a specific digestive function 1. Mucosa — Innermost moist epithelial layer that lines the lumen of the alimentary canal — Consists of three layers: a lining epithelium, lamina propria, muscularis mucosae — Three major functions are: Secretion of mucus, Absorption of the end products of digestion, Protection against infectious disease Lining Epithelium — Consists of simple columnar epithelium and mucus-secreting goblet cells — The mucus secretions: Protect digestive organs from digesting themselves — Ease food along the tract — Stomach and small intestine mucosa contain: Enzyme-secreting cells Lamina propria — Loose areolar and reticular connective tissue — Nourishes the epithelium and absorbs nutrients Muscularis mucosae — Smooth muscle cells that produce local movements of mucosa 2. Submucosa — dense connective tissue containing elastic fibers, blood and lymphatic vessels, lymph nodes, and ner ves 3. Muscularis externa — responsible for segmentation and peristalsis 4. Serosa — the protective visceral peritoneum — Replaced by the fibrous adventitia in the esophagus  MOUTH 1. Cheeks Oral or buccal cavity: 2. Lips (labia), Labial frenulum (attach to gums) — Is bounded by lips, cheeks, palate, and tongue 3. Hard palate - anterior part of roof of mouth — Has the oral orifice as its anterior opening (palatine bones) — Is continuous with the oropharynx posteriorly 4. Soft palate - posterior of roof of mouth (mucous membrane) To withstand abrasions: 5. Uvula - hanging portion of soft palate — The mouth is lined with stratified squamous (punching bag) epithelium 6. Palatoglossal arch & Palatopharyngeal arch: — The gums, hard palate, and dorsum of the tongue are a palatine tonsils bet ween arches slightly keratinized tounge Functions include: Superior surface bears three types of papillae: — Gripping and repositioning food during chewing Filiform : give the tongue roughness and provide friction — Mixing food with saliva and forming the bolus Fungiform : scattered widely over the tongue and give it — Initiation of swallowing, and speech a reddish hue — Note: Lingual frenulum secures the tongue to the floor Circumvallate : V-shaped row in back of tongue of the mouth Salivary glands Parotid — lies anterior to the ear bet ween the masseter muscle and skin — Parotid duct - opens into the vestibule next to the second upper molar Submandibular — lies along mandibular spact of the Sublingual — lies anterior to the submandibular gland under the tongue  TEETH Classification of Teeth: Teeth are classified according to their shape and function: Incisors - chisel-shaped teeth adapted for cutting or nipping Canines - conical or fanglike teeth that tear or pierce Premolars (bicuspids) and molars - have broad crowns with rounded tips and are best suited for grinding or crushing During chewing, upper and lower molars lock together generating crushing force Tooth Structure crown - above the level of the gums root - one to three projections into socket neck - bet ween crown and root on gumline dentin - hard shell of tooth pulp cavity - center of tooth pulp - lymph, blood, ner ve, connective tissue root canal - passage through roots to the pulp apical foramen - opening at the base enamel - covers the dentin on the crown cementum - covers dentin on the root Esophagus — Muscular tube going from the laryngopharynx to the stomach — Travels through the mediastinum and pierces the diaphragm — Joins the stomach at the cardiac orifice stomach — Chemicals breakdown of proteins begins and food is converted to chyme Cardiac region - surrounds the cardiac orifice Fundus - dome-shaped region beneath the diaphragm Body - midportion of the stomach Pyloric Region - made up of the antrum and canal which terminates at the pylorus; Pylorus—is continuous with the duodenum through the pyloric sphincter Greater curvature - entire extent of the convex lateral surface Lesser curvature - concave medial surface Lesser omentum - runs from the liver to the lesser cur vature Greater omentum - drapes inferiorly from the greater cur vature to the small intestine Rugae - folds in the inner lining of the stomach Blood supply: celiac trunk, and corresponding veins (part of the hepatic portal system)  Microscopic Anatomy of the Stomach Epithelial lining is composed of: — Goblet cells that produce a coat of alkaline mucus; The mucous surface layer traps a bicarbonate-rich fluid beneath it — Gastric pits contain gastric glands that secrete gastric juice, mucus, and gastrin Gastric glands of the fundus and body have a variety of secretory cells > Mucous neck cells - secrete acid mucus > Parietal cells - secrete HCI Small Intestine: Gross Anatomy — Runs from pyloric sphincter to the ileocecal valve — The bile duct and main pancreatic duct join the duodenum at the hepatopancreatic ampulla — The ileum joins the large intestine at the ileocecal valve Has three subdivisions: 1. duodenum 2. jejunum 3. ileum Small Intestine: Microscopic Anatomy — Structural modifications of the small intestine wall increase surface area: Villi - fingerlike extensions of the mucosa Microvilli - tiny projections of absorptive mucosal cells' plasma membranes Small Intestine: Histology — The epithelium of the mucosa is made up of: Absorptive cells and goblet cells Cells of intestinal crypts secrete intestinal juice Peyer's patches are found in the submucosa and are collections of lymphatic/wbc tissue Brunner's glands in the duodenum secrete alkaline mucus Pancreas - structure note: posterior to great curvature of the stomach 1. Head - enlarged portion in C-cur ve of the duodenum 2. Body - tapers off beneath the stomach 3. Tail - terminal part near the end 4. Pancreatic duct - merges with bile duct to duodenum (a. hepatopancreatic ampulla: merging of both) 5. Accessory duct - empties into duodenum, smaller  Pancreas - Histology 1. Made of glandular epithelial cells 2. Pancreatic islets (of Langerhans) (1% of all cells); a. hormones: glucagon, insulin, somatostatin 3. Acini - (99% of the cells in pancreas); a. mixture of enzymes called "pancreatic juice" Liver Superficially has four lobes : right, left, caudate, and quadrate The largest gland in the body Liver: Associated Structures The falciform ligament: — Separates the right and left lobes anteriorly — Suspends the liver from the diaphragm and anterior abdominal wall The ligamentum teres: — Is a remnant of the fetal umbilical vein — Runs along the free edge of the falciform ligament The lesser omentum — anchors the liver to the stomach The hepatic blood vessels — enter the liver at the porta hepatis Gallbladder — rests in a recess on the inferior surface of the right lobe; — stores bile for digestion of fats Bile — leaves the liver via: > Bile ducts, which fuse into the common hepatic duct > The common hepatic duct, which fuses with the cystic duct > These t wo ducts form the bile duct Liver: Microscopic Anatomy Lobules — are hexagonal shaped and the structural and functional units of the liver — Composed of hepatocyte (liver cell) plates radiating out ward from a central vein — Portal triads are found at each of the six corners of each liver lobule — Portal triads consist of a bile duct and — Hepatic Artery: supplies oxygen-rich blood to the liver — Hepatic portal vein - carries venous blood with nutrients from digestive viscera Liver sinusoids — enlarged, leaky capillaries located bet ween hepatic plates Kupffer cells — hepatic macrophages found in liver sinusoids Hepatocytes — functions include: Production of bile, Processing bloodborne nutrients, Storage of fat-soluble vitamins, Detoxification  Gallbladder — Thin-walled, green muscular sac on the ventral surface of the liver — Stores and concentrates bile by absorbing its water and ions — Releases bile via the cystic duct, which flows into the bile duct Large Intestine — Is subdivided into the cecum, appendix, colon, rectum, and anal canal — The saclike cecum: > Lies below the ileocecal valve in the right iliac fossa > Contains a wormlike vermiform appendix Colon; Has distinct regions: — ascending colon — hepatic flexure — transverse colon — splenic flexure — descending colon — sigmoid colon colon Anus — The transverse and sigmoid portions are anchored via internal sphincter - smooth muscle (involuntary) mesenteries called mesocolons external sphincter - skeletal muscle (voluntary) — The sigmoid colon joins the rectum — The anal canal, the last segment of the large intestine, opens to the exterior at the anus Mesenteries of Digestive Organs  Peptic Ulcer — erosion in a segment of the gastrointestinal mucosa, typically in the stomach (gastric ulcer) or the first few centimeters of the duodenum (duodenal ulcer), that penetrates through the muscularis mucosae. — Nearly all ulcers are caused by Helicobacter pylori infection or nonsteroidal anti-inflammatory drug (NSAID) use. Treatment: — Eradication of H. pylori (when present) — Acid-suppressive drugs — Methods of decreasing acidity include a number of drugs, all of which are effective but which vary in cost, duration of therapy, and convenience of dosing. In addition, mucosal protective drugs (eg, sucralfate) and acid-reducing surgical procedures may be used. — Drugs for decreasing acidity are used for peptic ulcer, gastroesophageal reflux disease (GERD), and many forms of gastritis. Some drugs are used in regimens for treating Helicobacter pylori infection. Drugs include: Proton pump inhibitors H2 blockers Antacids Prostaglandins Gastroentritis — occurs when there is a fecal-oral contact, ingestion of contaminated water or food, and person-to-person transmission, making it the main cause for norovirus and Shigella outbreaks. — The pathophysiology depends on the organism causing the disease. It can be caused by toxins like Staphylococcus aureus, which increase secretion leading to dehydration (e.g., Salmonella). Cytotoxins like Shigella and Clostridium difficile invade susceptible tissue and cause inflammatory diarrhea. Enterotoxins cause non-inflammatory diarrhea. Viruses frequently destroy villus surfaces. Parasites adhere to the mucosa. Treatment Overall, treatment and management of children with acute gastroenteritis involve: Rehydration (oral or IV) Diet selection Zinc supplementation Additional therapies like probiotics Antibiotics are considered in specific cases to reduce severity and duration or prevent complications like infection spread. Common antibiotics include: Ciprofloxacin TMP-SMX Erythromycin Metronidazole Note: Avoid antibiotics for infections caused by Bacillus cereus, Clostridium, and some Salmonella species.  CHAPTER 16: REPRODUCTIVE SYSTEM Reproduction — process by which genetic material is passed from one generation to the next Meiosis — produces sex cells — Sperm from male and egg from female join to form zygote — Zygote develops into embryo — Embryo develops into fetus Reproductive System - General Primary sex organs (gonads) - testes in males, ovaries in females Gonads produce sex cells called gametes and secrete sex hormones Accessory reproductive organs - ducts, glands, and external genitalia Sex hormones - androgens (males), and estrogens and progesterone (females) Sex hormones - General Sex hormones play roles in: — The development and function of the reproductive organs — Sexual behavior and drives — The growth and development of many other organs and tissues Male Reproductive System — The male gonads (testes) produce sperm and lie within a sac called the scrotum — Sperm are delivered to the exterior through a system of ducts: epididymis, ductus deferens, ejaculatory duct, and the urethra — Accessory sex glands: Empty their secretions into the ducts during ejaculation Include the seminal vesicles, prostate gland, and bulbourethral glands SCROTUM — Sac of skin and superficial fascia that hangs outside the abdominopelvic cavity at the root of the penis — Contains paired testicles separated by a midline septum — Intrascrotal temperature is kept constant by t wo sets of muscles: Cremaster - bands of skeletal muscle that elevate the testes Dartos - smooth muscle that allow rise and fall  TESTES Each testis is surrounded by t wo tunics: > The tunica vaginalis: derived from peritoneum > The tunica albuginea: the fibrous capsule of the testis Septa divide the testis into 250-300 lobules, each containing 1-4 seminiferous tubules Seminiferous tubules: — Produce the sperm (spermatogenesis) — Converge to form the tubulus rectus — The straight tubulus rectus conveys sperm to the rete testis — From the rete testis, the sperm leave the testis via efferent ductules — They then enter the epididymis Spermatogenesis — Spermatogonia > primary spermatocytes › secondary spermatocytes › spermatids > spermatozoa Sertoli cells — supply sperm cells with nutrients Testicular arteries branch from the abdominal aorta and supply the testes Spermatic cord - encloses PNS and SNS nerve fibers, blood vessels, and lymphatics that supply the testes The Anatomy of the Spermatozoa Three hundred million produced daily Anatomy: — Head: contains genetic material and acrosome > Acrosome has enzymes that aid sperm in penetrating covering of ovum — Middle piece: contains mitochondria — Tail: propels sperm Semen — Mixture of sperm cells and secretions — Provides energy to the sperm via fructose — Neutralizes acidity of vagina — Acts as a transport medium — Contains enzymes that activate sperm — Average volume is 2.5 to 6 mL — Seminalplasmin: destroys certain bacteria The Functions of Testosterone Path of Sperm — Controls development, growth, and Seminiferous tubules > Tubulus rectus > Rete maintenance of male sex organs testis > Efferent ductules > Epididymis — Stimulates muscle buildup and bone development — Causes sperm maturation — Causes thyroid cartilage enlargement — Produces body hair patterns Interstitial Cells — Surrounding the seminiferous tubules are interstitial cells (Leydig cells) that produce androgens  Penis — A copulatory organ designed to deliver sperm into the female reproductive tract — Prepuce (foreskin) : cuff of skin covering the distal end of the penis (removed during a circumcision) — Internal penis : the urethra and cylindrical bodies of erectile tissue — Erectile tissue : spongy net work of connective tissue and smooth muscle riddled with vascular spaces — Corpus spongiosum : surrounds the urethra and expands to form the glans and bulb of the penis — Corpora cavernosa : paired dorsal erectile bodies — Erection : during sexual excitement, the erectile tissues fill with blood causing the penis to enlarge and become rigid Epididymis — Non-motile sperm enter, pass through its tubes and become motile — Upon ejaculation the epididymis contracts, expelling sperm into the ductus deferens Ductus Deferens and Ejaculatory Duct — Propels sperm from the epididymis to the urethra — Vasectomy : cutting and ligating the ductus deferens, which is a nearly 100% effective form of birth control Urethra — Conveys both urine and semen (at different times) Consists of three regions: — Prostatic - portion surrounded by the prostate — Membranous - lies in the urogenital diaphragm — Spongy or penile - runs through the penis and opens to the outside at the external urethral orifice Accessory Glands: Accessory Glands: Accessory Glands: Seminal Vesicles Prostate Gland Bulbourethral Glands (Cowper's Glands) — Lie on the posterior wall of — Doughnut-shaped gland that — Pea-sized glands inferior to the bladder and secrete 60% encircles part of the urethra the prostate of the volume of semen inferior to the bladder — Produce thick, clear mucus — Join the ductus deferens to — Plays a role in the activation of prior to ejaculation that form the ejaculatory duct sperm neutralizes traces of acidic urine — Enters the prostatic urethra in the urethra and the penis during ejaculation — Can be palpated by digital rectal examination  female reproductive system — Ovaries are the primary female reproductive organs > Make female gametes (ova) > Secrete female sex hormones (estrogen and progesterone) — Accessory ducts include uterine tubes, uterus, and vagina — Internal genitalia : ovaries and the internal ducts (vagina, cer vix, uterus, fallopian tubes) — External genitalia : external sex organs (labia and clitoris) Ovaries Paired organs on each side of the uterus held in place by several ligaments — Ovarian - anchors the ovary medially to the uterus — Suspensory - anchors the ovary laterally to the pelvic wall — Mesovarium - suspends the ovary in bet ween — Broad ligament - contains the suspensory ligament and the mesovarium — Blood supply - ovarian arteries and the ovarian branch of the uterine artery — They are surrounded by a fibrous tunica albuginea, which is covered by a layer of epithelial cells called the germinal epithelium — Embedded in the ovary cortex are ovarian follicles — Each follicle consists of an immature egg called an oocyte — Cells around the oocyte are called: > Follicle cells (one cell layer thick) > Granulosa cells (when more than one layer is present) Ovulation - ejection of the oocyte from the ripening follicle Corpus luteum - ruptured follicle after ovulation Oogenesis — Begins in developing female fetus (700,000 produced) — Puberty: ovarian cycle begins — Primary oocyte: first meiotic division — Mature egg: second meiotic division Uterine Tubes (Fallopian Tubes) and Oviducts — Receive the ovulated oocyte and provide a site for fertilization — Empty into the superolateral region of the uterus via the isthmus — Expand distally around the ovary forming the ampulla — The ampulla ends in the funnel-shaped, ciliated infundibulum containing fingerlike projections called fimbriae  Uterus — A hollow, thick-walled organ located in the pelvis anterior to the rectum and posterosuperior to the bladder Body - major portion of the uterus Fundus - rounded region superior to the entrance of the uterine tubes Isthmus - narrowed region bet ween the body and cer vix Cervix - narrow neck which projects into the vagina inferiorly Cervical canal - cavity of the cer vix Supports of the Uterus Mesometrium - portion of the broad ligament that supports the uterus laterally Lateral cervical ligaments - extend from the cervix and superior part of the vagina to the lateral walls of the pelvis Uterosacral ligaments - paired ligaments that secure the uterus to the sacrum Round ligaments - bind the anterior wall to the labia majora Uterine Wall — Composed of three layers: Perimetrium - outermost serous layer; the visceral peritoneum Myometrium - middle layer; interlacing layers of smooth muscle Endometrium - mucosal lining of the uterine cavity — Has numerous uterine glands that change in length as the endometrial thickness changes The Menstrual Cycle Menstrual phase — Endometrial lining shed along with blood and mucus — Ovarian follicles begin development Preovulatory or proliferative phase — Secondary follicle matures into graafian follicle — Ovulation is rupturing of graafian follicle Postovulatory or secretory phase — Corpus luteum develops > Secretes estrogen and progesterone — If fertilization and implantation do not occur > Corpus luteum degenerates and new cycle starts — If fertilization and implantation occur > Corpus luteum maintained for four months  Function of Estrogen — Development of female secondary sex characteristics > Breast development, pubic hair, fat deposits, widening of the pelvic bone — Enlargement of: Uterine tubes, uterus, vagina, external genitalia Vagina — Thin-walled tube lying bet ween the bladder and the rectum, extending from the cervix to the exterior of the body — The urethra is embedded in the anterior wall — Provides a passageway for birth, menstrual flow, and is the organ of copulation Wall consists of three coats: 1. fibroelastic adventitia 2. smooth muscle muscularis 3. stratified squamous mucosa Mucosa near the vaginal orifice forms an incomplete partition called the hymen Vaginal fornix - upper end of the vagina surrounding the cervix External Genitalia: Vulva (Pudendum) — Lies external to the vagina and includes the labia, clitoris, and vestibular structures — Labia majora - elongated, hair-covered, fatty skin folds homologous to the male scrotum — Labia minora - hair-free skin folds lying within the labia majora; homologous to the ventral penis Greater vestibular glands: — Pea-size glands flanking the vagina — Homologous to the bulbourethral glands — Keep the vestibule moist and lubricated Clitoris — embryologically homologous to the penis — Erectile tissue hooded by the prepuce — The exposed portion is called the glans Mammary Glands — Produce milk in females — Contain 15 to 20 lobes with lobules — Lobules contain milk-secreting cells — Milk is conveyed through series of tubules — Areola: circular pigmented area around nipple  Pregnancy and Embryonic Development — Egg fertilization 12-24 hours after ovulation — Zygote: fertilized egg — Moves down uterine tube into uterus; Blastula — Zygote embeds in endometrium; placenta develops Primary germ layers — Ectoderm: skin and ner vous system — Mesoderm: muscles and bones — Endoderm: linings of organs and glands Amnion: fluid-filled sac — Attached to embryo by umbilical cord Parturition: childbirth Chapter 17: Urinary System Functions of the Urinary System Elimination of waste products Regulate aspects of homeostasis — Nitrogenous wastes — Water balance — Toxins — Electrolytes — Drugs — Acid-base balance in the blood — Blood pressure — Red blood cell production — Activation of vitamin D Organs of the Urinary system Kidneys Ureters Urinary bladder Urethra Location of the Kidneys — Against the dorsal body wall — At the level of T,2 to L3 — The right kidney is slightly lower than the left — Attached to ureters, renal blood vessels, and ner ves at renal hilus